The GRAIL Language and Operations
Tom Ellis, J. F. Heafner, William A. Sibley · RAND Corporation eBooks · 1969
The important organizational concepts of the flowchart language are the sequential flow of control, the hierarchy of subroutines, and the language (flow diagrams) that pictorially relates their interdependence. A fundamental facility of the man-machine interface is the automatic recognition of appropriate symbols, which allows the man to print or draw appropriate symbols freehand. GRAIL's text-editing features include placement, replacement, and deletion of characters, character-string insertion or deletion, and line deletion. Control functions include displaying text page-by-page, requesting specified display frames, moving symbols, and test line editing. The flowchart processes may be compiled and executed at CPU speeds or the man may control interpretative execution by direct stylus actions. He may use overlay displays or split screen displays to debug. This is the second part of a final report on GRAIL. (See also RM-5999 and RM-6002.)